JP6038877B2 - Aircraft seat with reinforcing strip for absorbing shock - Google Patents

Description

  The present invention is in the field of manufacturing aircraft cabin equipment for general aircraft, civil aircraft, helicopters, or military aircraft. More particularly, the present invention relates to the manufacture of aircraft seats that support one or more passengers and impact (forward impact) on passengers located in the back seat or the horizontal plane of the seat portion. Means for absorbing the impact on the passenger (downward impact).

  Aircraft seat volume has become a major concern for meeting the increasing number of passengers transported year by year. By reducing the unit volume of the seats, it is possible to reduce the spacing between the two rows of seats and increase the number of passengers that can be accommodated inside the aircraft, rather than being assigned to each passenger or for goods It is possible to expand the allocated space. As the aircraft gets better and better, it is possible to reduce the number of flights in a constant flow of passengers in one airway, and thus reduce greenhouse gas emissions due to fuel savings.

  By reducing the volume of the seat, the safety of passengers transported should not be reduced. Safety standards for aircraft seats are thorough, especially with respect to impact resistance.

  This limitation, which relates to impact resistance and passenger cushioning, has long produced aircraft seats intended for passengers using metal structures and deformable cushions. A structure composed of a large number of metal parts has resistance particularly at the time of impact. However, these structures are dense and the sheet is very heavy. A deformable cushion located in the horizontal plane of the seat part and the backrest allows a good cushioning of the passengers. However, these are also very dense, increasing the total weight of the sheet.

  The complexity of this type of sheet creates several problems during its manufacture, during its maintenance, or with respect to monitoring various parts. As the number of parts that make up an aircraft seat increases, the logistic and manufacturing processes of the seat become more complex and costly. Fixtures that hold these various parts together are often metal (usually made from stainless steel) to meet safety standards, resulting in higher weight sheets. Finally, with respect to the seat concept that each part must meet safety standards, the reduction in the number of parts limits the test to be performed and thus the total time required for seat approval. Therefore, the volume and weight of the sheet can be reduced by reducing the number of parts.

  Furthermore, the seat integrates historically very expensive functions in terms of weight and value and is no longer compatible with current cabin configurations. For example, the backrest slope is no longer usable if the space between the seat rows is reduced.

  A lightweight seat skeleton combined with a flexible backrest can eliminate these disadvantages. This seat shape combines the passenger's comfort with the flexible backrest and optionally with the seat part, and the mechanical strength of the skeleton, in order to take account of force criteria in air passenger transport. This separates the structural strength ensured by the single rigid component forming the skeleton and the passenger seat and backrest made of flexible material.

US Patent Application Publication No. 2008 / 0290715A1

  However, the restrictions on passenger cushioning in good safety conditions must always be taken into account. Accordingly, an object of the present invention is to provide a passenger located behind a seat at the time of a forward impact of an aircraft in which the head of the passenger located behind swings with respect to the rear portion of the backrest of the seat located in front of the passenger. It is to provide an aircraft seat according to the invention comprising means for providing a buffer. In a similar manner, the absorbing means arranged in the horizontal plane of the seat part makes it possible to hold the passenger during the downward impact of the aircraft.

Patent Document 1 describes a general example of a conventional aircraft seat.

  In order to achieve this object, the subject of the present invention is an aircraft seat in which the mechanical strength of the structure is ensured, in particular by a framework comprising a gap in the seat part and optionally in the horizontal plane of the backrest.

  According to the present invention, the aircraft seat is slightly rearward with respect to the backrest in the first embodiment of the present invention in order to absorb the swing of the passenger's head behind the aircraft during a severe forward impact. It is provided with a reinforcing strip made of energy-absorbing fabric, located and located on the back of the backrest. The same reinforcing strip may be placed in the horizontal plane of the seat portion to absorb the downward impact that would be very large in the case of a helicopter. The sheet may comprise these two strips.

  In one of the two main embodiments according to the invention, the energy-absorbing fabric is composed of a knitted product with a single yarn structure.

  In this case, the knitted product is advantageously of the jersey stitch type.

  A variation of this first embodiment is to use a plurality of yarns parallel to the knitted product.

  In the second main embodiment of the present invention, the energy absorbing fabric is woven with weft and warp yarns.

  It is preferable that the weft and the warp have almost the same strength.

  In a variant of this second embodiment according to the invention, the yarn is actually composed of a tight elastic yarn surrounded by a yarn that is relaxed but has a high tensile strength.

  In this case, which is a variant using a tensioned elastic yarn surrounded by a relaxing yarn having a high tensile strength, it is advantageous if the tensioned elastic yarn is made from a polyamide (eg Nylon®). It is.

  Materials used to construct the energy absorbing fabric of the reinforcing strip are polyetherimide fiber, polyetherketone fiber, high molecular weight polyethylene fiber, meta-aramid fiber and para-aramid fiber, natural fiber (flax, hemp, jute, etc.) And from the group consisting of polyamide fibers.

  The invention and its various technical features will be better understood by reading the following description, illustrated by the following eight figures.

FIG. 3 is a Cavalier view from the side and slightly from the front of the seat according to the invention. FIG. 2 is an exploded view of the same sheet as FIG. 1 having the same orientation. It is a cabarier rear exploded view of the same sheet as the previous two figures. FIG. 4 is a diagram of a knitted product used for a reinforcing strip of a sheet according to the present invention. FIG. 6 is a view of a variant of a knitted product used for a reinforcing strip of a sheet according to the invention. FIG. 2 is a view of a woven product used for a reinforcing strip of a sheet according to the present invention. FIG. 5 is a view relating to a variant of the yarn used in the woven fabric of the reinforcing strip of the sheet according to the invention. FIG. 5 is a view relating to a variant of the yarn used in the woven fabric of the reinforcing strip of the sheet according to the invention.

  Referring to FIG. 1, a sheet according to the present invention comprises a framework 1 that can be shaped, formed or assembled according to the choice of materials, and two flexible parts that form a backrest 2 and optionally a seat portion 3. Formed from. Seats for transporting passengers by aircraft provide multiple functions: dynamic resistance to impact and strong acceleration, passenger seats and backrests, and various accessories (small folding tables, magazine racks, Support for armrests, etc. Each of these functions corresponds to a sheet component that can be individually optimized to reduce the volume and total weight of the sheet.

  The first function of the sheet is structural strength. This function is ensured by the framework in the case of the present invention. Skeleton is understood to mean a rigid part of the seat that gives structural strength to the seat, and the backrest 2, seat portion 3, and attachment points do not play this role. The seat skeleton is usually hinged, but it can be lightweight while being rigid.

  FIG. 1 shows a minimum framework 1 of a sheet formed from a hollow tubular structure. The attachment points are located on the parts of the seat that are connected to the aircraft floor. In the case of a three-seater seat as shown in FIG. 1, the two central vertical bars 9 in the center of the backrest are directly against the seat mounting on the aircraft floor in the case of a non-hinge backrest. By connecting to the frame, the weight of the frame can be minimized.

  This fixation to the aircraft floor can be indirect, for example, by inserting the two lower bars of the skeleton 1 into a rail attached to the aircraft floor or by fixing to a rigid intermediate structure. Can be done. The rigid intermediate structure is fixed relative to the aircraft floor. By using a rigid aircraft structure, seat installation and maintenance can be facilitated.

  The second function of the seat is passenger accommodation. The seat backrest 2 and seat portion 3 are parts that are in direct contact with the passenger and may not contribute to the structural strength of the seat. These parts are fixed relative to the structure of the sheet itself, but can be much thinner to minimize the total weight of the sheet. The backrest 2 and optionally the seat part 3 are made from a flexible material. For example, a high tensile strength polyester woven product may be suitable. This stitching of the fibers makes it possible to obtain ergonomic shapes, in particular by marking compartment marks in the hollows of the back and buttocks.

  FIG. 2 shows the addition of the backrest 2 and the seat part 3 to the seat framework 1. These parts are very lightweight and are composed of a flexible material such as a polyester fiber weave. Added behind the backrest 2 is a strip 4 made of a flexible material having various properties and composed of an energy absorbing fabric, the production of which will be described in detail hereinafter. This is because the material constituting the backrest 2 cannot sufficiently cushion the passenger at the time of severe impact. The same strip (not shown) may optionally be added below the seat portion 3 if the seat must withstand a large downward impact.

  In FIG. 1 and FIG. 2, the accessories fixed to the frame 1 of the seat are also shown. These can be, inter alia, the cup holders 5 and 6 and the armrest 7.

  FIG. 3 also shows an exploded view of the same seat as viewed from the back. The skeleton 1, the backrest 2, the seat part 3 and the reinforcing strip 4 arranged behind the backrest 2 can be seen in this view. This figure includes a rack 8 that can be used, among other things, to place magazines or safety instructions.

  The main technical feature of the present invention is the use of a reinforcing strip 4 that must be much more deformable while being much more deformable than the backrest 2. The backrest 2 must have a gap or a concave rear surface in the middle of the framework 1 in order to form a space for the reinforcement strip 4 to deform upon impact.

  The principle of realizing the fibers constituting the reinforcing strip 4 and the strip optionally added below the sheet part is that the fiber is highly resistant and not very extensible, in other words high tensile strength or breaking strength In order to be able to absorb the impact smoothly, the fiber is combined with an elastic molded product. In absorbing the impact smoothly, the fabric is placed on the object to be stopped, i.e. the shape of the passenger's head located on the seat located behind the seat, on the backrest where the reinforcing strips are arranged. Deforms to carry. The fabric resists the object evenly and thereby absorbs the impact. In practice, the energy transferred in the event of an impact is not intrinsic to the impact point, but is spread over the entire contact surface between the fabric and the object. The applied pressure is greatly reduced to limit the stress experienced by the object.

  The selected fibers are agglomerated into yarns to allow fabric molding. Multiple fibers are agglomerated in the same yarn. The simplest yarns are para-aramid fibers (Kevlar® or Twaron®), polyetherimide fibers (Ultem®), polyetherketone fibers (PEEK®), polyamide fibers (Nylon) (Registered trademark)), natural fibers (flax, hemp, jute), or high molecular weight polyethylene fibers (Dyneema (registered trademark) or Spectra (registered trademark)). Tensile strength is a measure of the tensile strength that needs to be applied to break the fiber. The higher the tensile strength, the more resistant the fiber to higher tensile forces. If the fabric needs to have additional qualities, it is possible to mix multiple fibers in the same yarn, for example by adding meta-aramid (Nomex®) fibers for fire resistance It is.

  Once the yarn is constructed, it is shaped to form a fabric. Two main techniques, in other words knitting and weaving are possible. Knitting uses only a single yarn for the fabric surface, and weaving mixes multiple wefts and warps. Weaving can be used to mix multiple types of yarn, but the strength of the fabric is limited because the discontinuities of the yarn become weak spots on the fabric.

  Knitting makes it possible to ensure excellent mechanical strength in the resulting fabric, but limits the forming ability. In fact, knitted fabrics cannot be cut and sewn into other parts of the fabric without changing the mechanical performance of the knitting.

  Referring to FIG. 4, in the case of knitting, it is possible to obtain a relatively deformable fabric by jersey type stitches. Jersey stitches consist of making one flat knitting row followed by one back knitting row. The yarn 10 is wound around itself from one line to the next, and the loop leaves a large void space in the fabric surface.

  When tension is applied to the knitted fabric, the loop of yarn can be deformed to give a constant elasticity to the whole. If the tension is high and the deformation capacity of the stitch is exceeded, the yarn is subjected to tension loading and the tensile strength of the yarn plays a role. By using a single yarn for the entire knitting, tearing of the fabric from the break point of the yarn or at the junction between two yarns is avoided.

  Referring to FIG. 5, the knitted product mounting variation shown in FIG. 1 is configured by knitting a plurality of yarns 20 in parallel to the same fabric. The stitches remain the same, but instead of using only a single yarn, a plurality of yarns make up each stitch. Each yarn 20 is continuous over the entire surface of the fabric, but the properties of the yarn can be combined together. Examples include fire resistance, mechanical strength, or water repellency characteristics, among others. This variation is simpler to implement than mixing the fibers in the same single yarn, but does not mix the various fibers at similar intimacy. By using fine yarns, the interaction between the fibers can be enhanced. Again, jersey stitching can be used.

  Referring to FIG. 6, another alternative of the proposed principle according to the invention consists of weaving together various yarns, which are the weft yarn 40 and the warp yarn 50. The weft 40 and the warp 50 may be different, but it is necessary to ensure that the mechanical strength of the weft 40 and the warp 50 is equal. However, certain directions may be preferred compared to other directions. The woven product may be relatively loose and may provide some play between the weft 40 and the warp 50. This play does not relate to the elasticity of the fibers that make up the yarn, but gives the fabric an elasticity inherently related to the rearrangement between the yarns. An example of an embodiment may be a plain weave, in which case the weft and warp yarns are symmetrical, para-aramid yarn (Kevlar® or Twaron®), polyetherimide yarn (Ultem ( Registered trademark)), polyetherketone yarn (PEEK®), polyamide yarn (Nylon®), natural yarn (flax, hemp or jute), or high molecular weight polyethylene yarn (Dyneema®) Or it is produced from Spectra (registered trademark).

  In order to increase the elasticity of the woven product, it may be wise to construct a weft yarn using two yarns and a warp yarn using two yarns. Referring to FIG. 7A, an elastic center yarn 60 is used, but another high tensile strength yarn 62 surrounds this yarn 60 in a very broad manner. The elastic yarn 60 may be, for example, a nylon yarn (polyamide 6-6). The high tensile strength yarn 62 includes para-aramid yarn (Kevlar (registered trademark) or Twaron (registered trademark)), polyetherimide yarn (Ultem (registered trademark)), polyether ketone yarn (PEEK (registered trademark)), polyamide yarn ( Nylon®), natural yarn (flax, hemp or jute), or high molecular weight polyethylene yarn (Dyneema® or Spectra®). The high tensile strength yarn 62 is wound or twisted around the elastic yarn 60 located at the center.

  Referring to FIG. 7B, when tension is applied to the fabric, the elastic yarn 60 disposed at the center is stretched, but the high tensile strength yarn 62 located in the periphery is deformed to form the elastic yarn 60. The closer you are. If the tension exceeds the deformability of the centrally located elastic yarn 60, then the yarn 62 having a high tensile strength will be taut and then give a very high mechanical strength to the fabric constructed thereby.

Implementation and Benefits During forward impact of the aircraft, the cushioning of the passenger's head at the rear of the front seat backrest becomes more efficient as the fabric part becomes more elastic. Similarly, during a downward impact, passenger cushioning occurs in the horizontal plane of the seat portion of the seat, which becomes more efficient as the elasticity of the strip added under the seat portion becomes higher. Become. In fact, buffering is based on converting kinetic energy from passengers into elastic energy of fabric parts. Passenger impact, in other words, the force transmitted to the passenger is minimized when moving from cruising speed to rest, and the buffer is deployed over as large a time scale as possible. Thus, a sufficiently low modulus of elasticity that results in a very highly elastic fabric allows the impact to develop over time and minimize the impact perceived by the passenger. By dividing the tensile strength of the fibers used to make up the yarn by the linear density of the fibers, the strength of the fabric that is not torn upon impact is defined. Thus, the fabric can withstand the impact of passengers fired at full speed due to forward impact during emergency landing of the aircraft, or in the case of a downward impact in the case of strips placed under the seat portion. it can.

  The breaking strength is generally low for elastic fibers. This elasticity is obtained by allowing the individual filaments to slide relative to each other in the same yarn. The low binding force between the filaments is a problem when resisting breakage. This is because individual filaments break apart at low force levels. Aramid fibers (Kevlar® or Twaron®), polyetherimide fibers (Ultem®), polyetherketone fibers (PEEK®), polyamide fibers (Nylon®), By using yarns with very high tensile strength, such as natural fibers (flax, hemp or jute) or high molecular weight polyethylene fibers (Dyneema® or Spectra®), elasticity and tension It is possible to combine these conflicting characteristics of strength and to combine these characteristics by forming an elastic knitted product or by using a mixed woven product. Knitting is the formation of a yarn into stitches using only a single yarn for the entire fabric. The use of a large size single yarn ensures the overall mechanical strength and avoids yarn breaks. By using jersey stitches, this structure allows this elasticity to be obtained regardless of the elasticity of the yarn. Alternatively, the use of a woven product combining an elastic yarn and a relaxed yarn having high tensile strength can result in the same result. The use of an elastic structure and a high tensile strength yarn makes it possible to combine the reduction speed for passengers with the excellent mechanical strength of the fabric parts.

DESCRIPTION OF SYMBOLS 1 Frame 2 Backrest 3 Seat part 4 Reinforcement strip 5 Cup holder 6 Cup holder 7 Armrest 8 Rack 9 Center vertical bar 10 Single thread 20 Multiple threads 40 Weft 60 Elastic thread 62 High tensile strength thread

Claims (14)

An aircraft seat,
A framework (1) for ensuring the mechanical strength of the aircraft seat structure;
An aircraft seat comprising a backrest (2) of the aircraft seat and two flexible parts forming a seat portion (3);
The aircraft seat is made from an energy-absorbing fabric disposed behind the backrest (2) to absorb the swaying of the passenger's head located in the seat behind the aircraft during severe impacts. Reinforced strip (4) and an energy-absorbing fabric disposed under the seat portion (3) to cushion the passenger's body located on the seat during a severe downward impact of the aircraft were further comprising a second reinforcing strip, a, and said reinforcing strip (4), the backrest (2) good remote deformable, it is highly resistant, and / or the second reinforcement strip Is a sheet that is more deformable than the sheet portion (3) and has high resistance . The seat according to claim 1 , wherein the frame (1) has a gap in the center of the backrest (2). The seat according to claim 1 or 2 , characterized in that the backrest (2) has a concave rear surface to form a space for the deformation of the reinforcing strip (4). The seat according to any one of claims 1 to 3 , wherein the reinforcing strip (4) is located slightly behind the backrest (2). The sheet according to any one of claims 1 to 4 , characterized in that the second reinforcing strip is located slightly below the sheet part (3). The reinforcing strip (4), the backrest (2) good remote deformable be composed of fabric comprising high tensile strength yarns shaped to constitute the fabric, and / or the second reinforcing strip, said seat portion (3) any one of claims 1 to 5, characterized in that they are composed of fabric, including a high tensile strength yarn that is shaped to constitute a fabric deformable than The sheet according to item. The sheet according to claim 1, wherein the energy-absorbing fabric of the reinforcing strip (4) and / or the second reinforcing strip is composed of a knitted product having a single yarn (10) structure. The sheet according to claim 7 , wherein the knitted product is of a jersey stitch type. The sheet according to claim 7 or 8 , wherein the knitted product is composed of a plurality of parallel yarns (20). The sheet according to claim 1, characterized in that the reinforcing strip (4) and / or the energy-absorbing fabric of the second reinforcing strip is woven with weft (40) and warp (50). 11. Sheet according to claim 10 , characterized in that wefts (40) and warps (50) having substantially the same breaking strength are used. The yarn used to constitute the weft yarn (40) and the warp yarn (50) is actually a yarn (62) having a high tensile strength, but a tight elastic yarn surrounded by a relaxed yarn. The sheet according to claim 10 or 11 , comprising (60). 13. A sheet according to claim 12 , characterized in that the taut elastic thread (60) is made of polyamide. The energy absorbing fabric of the reinforcing strip (4) and / or the second reinforcing strip comprises polyetherimide fiber, polyetherketone fiber, high molecular weight polyethylene fiber, meta-aramid fiber and para-aramid fiber, natural fiber, and polyamide fiber. The sheet according to any one of claims 1 to 13 , wherein the sheet is made of a yarn made of a material that forms a part of a group including.

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